"It's all these grieving people who then just behave like lunatics."

While the full title of Shakespeare's comedy Twelfth Night, orWhat You Will, is seldom cited, some scholars believe the subtitle was the play's original name. "Twelfth Night" itself connotes the end of the Christmas season, in Elizabethan times a revel-filled occasion Shakespeare perhaps wrote the play to mark. In either case, the title emits an air of anarchy -- one of the qualities Karla Boos seems to like about it best.

Boos, artistic director of Quantum Theatre, has set peripatetic Quantum's new production of Twelfth Night in a hidden but accessible outdoor spot. It's the asphalt-paved courtyard of a former West Penn Hospital Foundation research building located where Bloomfield's Gross Street ends, in the valley separating that neighborhood from Shadyside.

The stark, concrete-clad four-story building represents the initially inflexible world of the countess Olivia and Duke Orsino, the aristocrats in Shakespeare's Illyria. A similarly featureless retaining wall, meanwhile, holds back a green, half-wild Bloomfield hillside -- and those barely contained woods are the very metaphor for nearly every other role in this music-filled farrago of twin siblings, cruel practical jokes and cross-gender disguise.

There's tragedy in the play -- some real, some imagined. But, as Boos notes, "It's all these grieving people who then just behave like lunatics."

Thus three male characters (including Orsino) long for Olivia, who herself longs only for a young man who's actually a young woman, named Viola, in disguise; one subplot is homoerotic; and at least two other storylines involve the dissolute machinations of a character named Sir Toby Belch. Meanwhile, the play's most abused character -- Olivia's steward, Malvolio -- is by Boos' reckoning the only sane one in the bunch.

For added disportment, characters perform Shakespeare's iconic Twelfth Night songs and Boos unveils a novel (and musical) stratagem for dealing with the noise of the nearby trains likely to pass by at least once per performance. (Don't worry, you'll be amused.) Boos also encourages audience members to bring refreshments for pre-show and intermission picnicking -- just to help everyone feel as frolicsome as the characters.